I have no idea, I went and borrowed the bits that looked like the right size. For all I know they could be for only wood.

I guess I will just run to the store and ask for the best bit for the job. The drill I have sucks too. If the drill isnt fast enough would that make it pointless to even try?

 

Bits should feel sharp, if they dont they arent, and yes I would recommend getting one specifically for the job if you arent sure ofthequality.
The drill should be fast, but I suppose it could work if it wasnt, but it would certainly make it harder.
Typically you want to remove a little bit of material at a time, but very quickly, so you arent putting stress on the bit. Sounds strange, I know, but what I mean is you shouldnt be forcing the bit in there with excessive pressure, it should be capable of doing its job of cutting the metal.
A slow drill or dull bit are going to make that difficult.